Align event_tags partition lifecycle with events

test/parrhesia/storage/adapters/postgres/query_plan_regression_test.exs

@@ -64,7 +64,8 @@ defmodule Parrhesia.Storage.Adapters.Postgres.QueryPlanRegressionTest do
       )
 
     plan = Enum.map_join(explain.rows, "\n", &hd/1)
-    assert plan =~ "event_tags_h_value_created_at_idx"
+    assert plan =~ "Index Scan using event_tags_"
+    refute plan =~ "Filter: ((name)::text = 'h'::text)"
   end
 
   test "#i-heavy query plan uses dedicated event_tags i index" do
@@ -111,7 +112,8 @@ defmodule Parrhesia.Storage.Adapters.Postgres.QueryPlanRegressionTest do
       )
 
     plan = Enum.map_join(explain.rows, "\n", &hd/1)
-    assert plan =~ "event_tags_i_value_created_at_idx"
+    assert plan =~ "Index Scan using event_tags_"
+    refute plan =~ "Filter: ((name)::text = 'i'::text)"
   end
 
   defp persist_event(overrides) do

test/parrhesia/storage/archiver_test.exs

@@ -15,7 +15,7 @@ defmodule Parrhesia.Storage.ArchiverTest do
     assert is_list(partitions)
   end
 
-  test "ensure_monthly_partitions creates named monthly partitions" do
+  test "ensure_monthly_partitions creates aligned monthly partitions for events and event_tags" do
     assert :ok =
              Archiver.ensure_monthly_partitions(reference_date: ~D[2026-06-14], months_ahead: 1)
 
@@ -25,6 +25,9 @@ defmodule Parrhesia.Storage.ArchiverTest do
 
     assert "events_2026_06" in monthly_partition_names
     assert "events_2026_07" in monthly_partition_names
+
+    assert table_exists?("event_tags_2026_06")
+    assert table_exists?("event_tags_2026_07")
   end
 
   test "archive_sql builds insert-select statement" do
@@ -35,6 +38,21 @@ defmodule Parrhesia.Storage.ArchiverTest do
   test "drop_partition returns an error for protected partitions" do
     assert {:error, :protected_partition} = Archiver.drop_partition("events_default")
     assert {:error, :protected_partition} = Archiver.drop_partition("events")
+    assert {:error, :protected_partition} = Archiver.drop_partition("event_tags_default")
+    assert {:error, :protected_partition} = Archiver.drop_partition("event_tags")
+  end
+
+  test "drop_partition removes aligned event_tags partition for monthly event partition" do
+    assert :ok =
+             Archiver.ensure_monthly_partitions(reference_date: ~D[2026-08-14], months_ahead: 0)
+
+    assert table_exists?("events_2026_08")
+    assert table_exists?("event_tags_2026_08")
+
+    assert :ok = Archiver.drop_partition("events_2026_08")
+
+    refute table_exists?("events_2026_08")
+    refute table_exists?("event_tags_2026_08")
   end
 
   test "database_size_bytes returns the current database size" do
@@ -48,4 +66,12 @@ defmodule Parrhesia.Storage.ArchiverTest do
       Archiver.archive_sql("events_default; DROP TABLE events", "events_archive")
     end
   end
+
+  defp table_exists?(table_name) when is_binary(table_name) do
+    case Repo.query("SELECT to_regclass($1)", ["public." <> table_name]) do
+      {:ok, %{rows: [[nil]]}} -> false
+      {:ok, %{rows: [[_relation_name]]}} -> true
+      _other -> false
+    end
+  end
 end